Gasoline and method of making the same



Patented Sept. 8, 1936 UNITED STATES PATENT OFFICE Gasonmn AND mrrnon or MAKING THE SAME No Drawing. Original application January 16, 1928, Serial No. 247,256. Divided and this application February 21, 1936, Serial No. 65,172

Another object is to produce a cracked asoline which is stable in color, and this is accomplished by preventing the formation of soluble colored compounds in the gasoline on standing.

A further object is to preserve the anti-knock quality of the cracked gasoline or, in other words, to prevent the formation of soluble detonating compounds, said compounds being closely related to the gum constituents.

With the foregoing objects in view, we will proceed to point out some of the undesirable characterlstics of cracked gasoline, how our invention overcomes these undesirable characteristics, and finally compare our methods with' those previously used and point out the advantages of the methods we have discovered.

Cracked gasolines have the property, even' when freshly made, of depositing dark brown gummy residues on surfaces from which they are slowly evaporated. The composition of the deposit is not fully understood but has become known in the trade as gum and will hereafter be referred to by this term. The chemical reaction producing the gum is also not fully understood, but we believe it is an oxidation reaction either internal or external; internal oxidation being that taking place within the material, itself, and external that caused by some external power as oxygen from the air or the rays of light.

Another property commonly notedin gasolines made from cracked products is formation of gum in solutions which is evidenced by an increase in the deposit left by evaporating a sample that has stood for some time in comparison with that formed by the original material before aging. The compounds which have the power then of producing gum when the fresh sample is evaporated apparently proceed to form gum in solution when the same product is allowed to stand.

A further property also related to 'gum is the detonation characteristic. It is related in that a gasoline which has accumulated appreciable quantities of gum in solution also shows a greater tendency to knock. 'It is important to prevent the formation of compounds which promote detonation in cracked fuels because it is by virtue of the cracked orunsaturated nature of these fuels that they have become recognized as antikaock gasolines.

Our invention overcomes the above mentioned gum and detonation problems by inhibiting the reactions which produce gum either when the fresh sample is evaporated or when the same product is allowed to age before evaporation; and, as previously pointed out, there being a close relationship between these properties, by preventing or inhibiting the reactions which produce gum, we also suppress the formation of compounds causing detonation.

The invention which we will hereafter describe is concerned with the prevention of the reactions which cause formation of gum rather than the remedy after the harm or effect has been caused, for we have found that once the gum has accumulated in solution, it is very diflicult to re- 'move without drastic treatment. But, on the other hand, by simple treatment of the fresh cracked gasoline by our method before the harm has resulted, it is very easy to inhibit the formation ofgunrwhen the sample is evaporated or when it is allowed to stand.

In order to overcome these undesirable properties of cracked gasoline, we add to the gasoline a small quantity of certain organic compounds which we have discovered have theproperty of inhibiting formation of the undesirable gum. The nature of the inhibiting reaction, whereby. these organic compounds function to prevent the formatlon of gum, is not clearly understood, but we characterize the compounds as inhibitors, antioxidants, negative catalysts, or simply anti-gum formers. Within the group of anti-gum formers we have found the following to be useful:

Ortho-aminophenol, meta-aminophenol, paraaminophenol, para-benzylaminophenol, beta-hydroxyethylaminophenol, para-dimethylaminophenol, -benzylamino-2-cresol', 2-amino-5- hydroxytoluene, 5-amino 2 hydroxytoluene, para-phenylenediamine, meta-phenylenediamine, orthophenylenediamine, and benzidene. In order to classify these compounds and not limit ourselves to those specified above, we prefer to distinguish them as aromatic amines and aminophenols and the derivatives of either class.

The quantity of anti-gum former required to accomplish our purpose varies somewhat depending on the nature of the gasoline to be treated. We may use from two to fifty milligrams per 100 cubic centimeters of the gasoline, but we prefer to use approximately ten milligrams per 100 cubic i then added, in solution, to the gasoline.

centimeters. These may be added to the gasoline directly or it may be previously dissolved in a solvent such as acetone, benzol or ether. etc., and The latter method has been found to be advantageous where the material is diflicultly dissolved.

In actual practice we prefer to treat a raw cracked gasoline direct from the still with" approximately ten milligrams of ortho-aminophenol per 100cubic centimeters. By this treatment we have found that the treated gasoline will deposit no appreciable gum when immediately eva rated or after aging for long periods. I

We wish to point out that our process is equally applicable to any gum forming cracked gasoline, whether previously treated or not, as well as the raw cracked gasoline mentioned in our preferred form. In fact our process is valuable for treating fuels which have been acid treated or filtered through fuller's earth provided they tend to form gum on storage, and also for blended fuels such as those containing products not strictly from petroleum among which may be mentioned those derived from coal tar or shale oil.

Prior to our invention the methods used consisted in treating the cracked gasoline with polymerizing agents such as sulphuric acid, fullers earth, etc., whereby the gum forming constituents were polymerized and removed as sludge. Such methods are costly because they require special equipment, large quantities of treating reagents and considerable time for the operations. Also the prior methods removed products which are .valuable as fuel, especially for anti-knock purposes. Our process on the other hand is simple in that any tankor similar equipment available in the ordinary refinery may be used for adding the anti-gum former and the time required is of no important consideration; it is inexpensive, in that the quantity of treating material is very small since it enters into the reaction more in the nature of a catalyst than in 'quantitive proportions, and lastly no valuable constituents of the gasoline are lost as sludge.

This application is a division of our copending application No. 247,256 filed January 16, 1928.

We claim:

1. The method of preserving cracked hydrocarbon distillates which normally tend to develop gums on storage, which comprises incorporating therein, prior to such deterioration, a small proportion of an aminophenol sufficient to retard gum formation therein.

2. A motor fuel product comprising cracked gasoline which normally tends to deteriorate and develop gums on storage to which has been added a small proportion of an aminophenol in quantities sumcient to retard such gum formation.

3. A motor fuel product consisting substantially entirely of cracked hydrocarbon distillates normally tending to deteriorate and develop gums, said product containing a small proportion of an organic reducing agent having an aminohydroxy aromatic radical to inhibit said gum formation. A

4. A motor fuel product consisting substantially entirely of cracked hydrocarbon distillates which normally tend to deteriorate and develop gums, said product containing a small proportion of an organic reducing agent having an aminophenol radical, as a result of which its tendencies to deteriorate and develop gums are inhibited.

5. The method of treating a motor fuel containing highly unsaturated hydrocarbon constituents which normally tend to develop gums on 7. A motor fuel product comprising cracked hydrocarbon distillates of the character of gasoline which normally tend to deteriorate and develop gums on storage, said product containing an added small proportion of an organic reducing agent having an aminohydroxy aromatic radical,

as a result of which its tendencies to deteriorate and develop gums are substantially inhibited.

8. The method of treating a motor fuel containing unsaturated cracked hydrocarbons which normally tend to form gum on storage, which comprises adding to said motor fuel prior to the formation of gum an organic reducing agent having an aminophenol radical, in quantities sufflcient to retard said gum formation.

9. A cracked gasoline normally tending to deteriorate and develop gummy substances upon storage and containing a para aminophenol in quantity sufllcient to retard such gum formation.

10. The method of preserving a liquid motor fuel comprising highly unsaturated hydrocarbons which normally tend to deteriorate and develop gums upon storage, which comprises dissolving in said motor fuel prior to the formation of gum a para aminophenol in quantities suflicient to retard such deterioration and gum formation.

11. The method of treating a motor fuel containing unsaturated cracked hydrocarbons which normally tend to form gum on storage, which comprises adding to said motor fuel a para aminophenol in quantities sufilcient to retard said gum formation.

12. A cracked gasoline normally tending to deteriorate and develop gummy substances upon storage and containing para aminophenol in quantity sufficient to retard such gum formation.

13. The method of treating a motor fuel containing unsaturated crackedhydrocarbons which normally tend to form gum on storage, which comprises adding to said motor fuel prior to the formation of gum para aminophenol in quantity sufficient to retard said gum formation.

14. The method of treating a motor fuel containing unsaturated cracked hydrocarbons which normally tend to form gum on storage, which comprises adding to said motor fuel an ortho aminophenol in quantity suflicient to retard such gum formation.

15. A motor fuel product comprising cracked hydrocarbon distillates which normally tends to deteriorate and develop gummy substances upon storage and containing para aminophenol sufficient in quantity to exerta substantial inhibiting action on deterioration and gum formation therein.

16. A motor fuel comprising cracked hydrocarbon distillates normally tending to deteriorate and develop gummy substances on storage and containing aminophenol having an alkylated benzene nucleus, in quantities sufficient to substantially retard said gum formation.

17. The method of preserving a motor fuel comprising craoked hydrocarbon distillates which normally tend to develop gum on storage, which comprises-incorporating therein, prior to such deterioration, a small proportion of aminophenol having an alkylated benzene nucleus, in quantity sufflclent ,to retard gum formation in said motor fuel.

18. The method of treating a motor fuel containing unsaturated cracked hydrocarbons which normally tend to form gum on storage, which comprises adding to said motor fuel 5-amino-2- 10 hydroxy-toluene in quantity suflicient to retard said gum formation.

19. A motor fuel product comprising a hydrocarbon distillate containing unsaturated hydrocarbons which normally tend to deteriorate and develop gums on storage, said product containing an added small proportion of 5-amino-2-hydroxy-toluene as a result of which its tendency to deteriorate and develop gums is substantially inhibited.

HARRY T. BENNETT.

LE ROY G. STORY. 

